v. (past sank or sunk; past part. sunk or as adj. sunken) 1 fall or come slowly downwards. 2 disappear below the horizon. 3 a go or penetrate below the surface esp. of a liquid. b (of a ship) go to the bottom of the sea etc. 4 settle comfortably. 5 a decline in strength etc. b (of the voice) descend in pitch or volume. 6 cause or allow to sink or penetrate. 7 cause (a plan, person, etc.) to fail. 8 dig (a well) or bore (a shaft). 9 engrave (a die). 10 invest (money). 11 a knock (a ball) into a pocket or hole in billiards, golf, etc. b achieve this by (a stroke). 12 overlook or forget (sank their differences). n. 1 plumbedin basin, esp. in a kitchen. 2 place where foul liquid collects. 3 place of vice. sink in 1 penetrate or permeate. 2 become understood. [Old English] sinker n. weight used to sink a fishingline or soundingline.


